According to the latest data published in august 2008 by the Council for Economic Planning and Development (Taiwan), the social structure of Taiwan is getting an aging society, and the demand of the walking assistive apparatus to prevent the elder and the people with physical disabilities from falling down is getting higher and higher.
The Taiwan patent 395305 discloses a controller of a contacting surface of a motor. The controller keeps the contact force to the surface by calculating an external force contacting with the surface according to the angle variation of a torque spring. However, the controller does not have a function to be actively commanded by the master. Therefore, the controller lacks the adaptability when the situation is urgent.
The Taiwan patent 1274239 discloses a predictor capable of accommodating the force of a motor. The predictor predicts the external force imposed by a user according to the rotation speed of the motor, and further follows the will of the user to speed up or down to the motor. However, the predictor does not have a function be actively commanded by the master either, and lacks the adaptability when in a positive feedback environment.
The U.S. Pat. No. 6,518,718 discloses an auto-decelerating system of a motor. The system predicts the external force according to the current variation of the motor, and adjusts the force of the motor by controlling the motor voltage. However, the controller only compliance control one single motor and can not compliance control the whole platform.
The U.S. Pat. No. 7,386,365 discloses a controller of a surgical robot arm. The terminal robot arm is affected by operating the control-end robot arm. The terminal robot arm sends back the information of the force and position of the motor to the motor of each control-end robot arm correspondingly. However, the controller does not have a function to actively commands by the master either, and the controller lacks the adaptability when the situation is urgent.
In summary, the techniques relate to the walking assistive apparatus mostly lack the combination of a compliance controller and a self-navigator, and thus these prior arts could not achieve the functions of predicting the user force, self-navigating, compliance motion controlling, obstacle avoidance, slope surface walking assistant and omni-directional moving. Thus the elderly usually feel inconvenience and not humanized when using the conventional walking assistive apparatus.